Organic Extracts Research Articles

Antibacterial Activity of Organic Solvents Extract on Fruits and Leaves of Black Mulberry against Streptococcus Mutans and Lactobacillus Acidophilus

ABSTRACT Background: The mulberry leaves have far more flavonoids than other berries while having much less catechin. The aim and objective of this study were assessment of the antibacterial efficacy of ethanolic extract of mulberry fruit and leaves on Streptococcus mutans and Lactobacillus acidophilus. Material and Methods: The ethanol extracts of fruits and leaves of black mulberry will be prepared in the institute. The minimal inhibition concentration will be determined against the Streptococcus mutans and Lactobacillus acidophilus. Results: A 25% mulberry leaves and 100% mulberry fruit have shown less Streptococcus mutans and Lactobacillus count. A concentration of 25% mulberry leaves has shown less Streptococcus mutans count. A concentration of 25% mulberry leaves and 100% mulberry leaves has shown no lactobacillus count. Conclusions: The results indicated that phenolics and flavonoids exerted a noteworthy influence in antioxidant examinations, given that the quantities of these compounds were directly proportional to the level of activity observed.

Green liquid-liquid microextraction for quantification of ketamine and metabolites in human urine by gas chromatography-mass spectrometry.

This study aimed to develop and validate a green method for the detection of ketamine and its metabolites in human urine samples and subsequently determine which metabolite is more suitable for judgment of ketamine abuse. Ketamine and its metabolites were extracted from urine samples with 1-undecanol using liquid-liquid microextraction based on the solidification of floating organic droplet extraction. The extracts were directly analyzed using gas chromatography-mass spectrometry (GC-MS) without derivatization. The sample pretreatment procedure prior to GC-MS analysis was simple, fast, and required little solvent consumption. Parameters that affect the extraction efficiency, including pH of the urine sample and centrifugation speed, were optimized. Under the optimized conditions, the limits of detection for norketamine, dehydronorketamine, and ketamine were 1.5, 1.7 and 1.0 ng/mL, respectively. The method was used to analyze eight real urine samples from drug abusers and exhibited acceptable accuracy and precision. By analyzing real samples, this study revealed that detection of dehydronorketamine in urine samples for the judgment of ketamine abuse may be more suitable than detection of norketamine or ketamine. The method used in this study addresses the need for green analytical techniques in toxicology.

Virucidal potential of oleuropein identified in Castana sativa shell: insight from in vitro and in silico studies

ABSTRACT In this report, Castanea sativa shell extracts have been investigated for their activity against Herpes Virus type 2 (HSV-2). Among four organic extracts only 75% ethanol extract demonstrated activity against HSV-2 with a 50% inhibitory concentration of 6.45 μg/mL. The study of the mechanism underlying the antiviral activity demonstrated this extract strongly inhibits HSV-2 by direct contact and moderately protects the cell from virus recognition and binding. The active compound has been identified as oleuropein by HPLC-DAD-ESI-MSn. This compound which is widely known in the Oleaceae family has been identified in the chestnut shells for the first time. The in vitro results of the mechanism underlying anti HSV-2 action were confirmed by an in silico study which revealed a strong binding free energy of −9.08 kcal/mol between oleuropein and the glycoprotein D of HSV-2. In summary, our findings suggest that C. sativa shells may constitute a promising natural source of anti-HSV-2 agents.

EXPRESS: Challenging Biological Samples and Strategies for DNA Extraction.

Despite the significant progress of DNA profiling in forensic science, the extraction of DNA from challenging samples remains a formidable obstacle in forensic laboratories. Particularly, hard tissues (bones, teeth, hair, and nails), formalin-fixed tissues, and contaminated samples pose considerable difficulties. DNA extraction from such samples is often complicated, resulting in scanty, degraded, and contaminated DNA. Moreover, the presence of inhibitors from the surrounding environment further hinders DNA quantification and amplification, presenting additional challenges. This review article delves into the molecular basis of these challenges and examines the mechanistic principles underlying standard DNA extraction protocols. To overcome these obstacles, skilled efforts and additional pre-processing techniques are generally required before organic or silica column-based DNA extraction. Such techniques may involve scraping the waste, sample cleaning with detergents, disinfecting, demineralization of bones and teeth, long proteolytic enzyme treatment, in some cases, harsh methods like hot alkali treatment, tailored to the specific sample type. By addressing these challenges and understanding the molecular intricacies involved in DNA extraction, forensic scientists can improve the reliability and success rate of DNA analysis from difficult forensic samples. This review serves as a comprehensive resource for understanding the complexities of DNA extraction and offers potential solutions for recovering the DNA from highly challenging samples.

Effect of alkaline-acid treatment of different rank coals on the extraction

ABSTRACT Coal resources are vital for global energy supply but are affected by impurities. Organic solvent extraction can be used to prepare ash-free coal. To improve coal quality and boost the yield of the extracted material, the research focused on optimizing the demineralization process. The influence of alkaline-acid treatment on the extraction yield of different coal ranks was investigated using N-methyl-2-pyrrolidone (NMP) as the extractant. Fourier Transform Infrared Spectroscopy (FTIR) was used to examine the changes in functional groups and structural modifications in coal samples before and after demineralization. The alkaline-acid pretreatment process achieved an ash removal rate of up to 69.1%. Additionally, the optimal conditions for the sodium hydroxide and hydrochloric acid leaching processes were determined. Pretreatment affected the extraction yields of different coal ranks differently. Anthracite extraction yield increased from 6.4% to 13.6%, while the extraction yields of bituminous coal and lignite declined. Guidance is provided on how pretreatment affects coals of different ranks, and the structural changes during the extraction process are described in detail.

In vitro Evaluation of Antibiotics, Antibacterial Chemicals, Bioagents, and Organic Extracts for the Management of Bacterial Blight of Rice (Xanthomonas oryzae pv. oryzae)

Xanthomonas oryzae pv. oryzae, the pathogen causing bacterial blight of rice, is an age old disease that has caused serious threat to the crop. Hence, this experiment was conducted using different commercially available antibiotics, antibacterial chemicals, bioagents and organic extracts to test their efficacy against the pathogen and devise management strategies against the disease. In vitro efficacy studies revealed that, among the antibiotics, 2-bromo 2-nitro propane 1,3-diol (Bacterinashak) (8.33 mm), an immunomodulator and among the antibacterial chemicals, copper oxychloride 50% WP (Blitox-50) (9.08 mm) showed a good inhibition of the bacterium and were statistically better than other treatments. Pseudomonas fluorescens (23.67 mm) among the bioagents and sea weed extract (Humicil) (6.50 mm) among the tested organic extracts were found to be significantly superior in inhibiting the pathogen. In summary, all the treatments exhibited a strong inhibition over the control and these could be used as potential strategies to manage the disease under field conditions.

Development of HPLC-DAD method for the separation and simultaneous determination of ten antibiotic residues in food and environmental samples using surface floating organic droplet-based air-assisted liquid-liquid micro-extraction.

Development of HPLC-DAD method for the separation and simultaneous determination of ten antibiotic residues in food and environmental samples using surface floating organic droplet-based air-assisted liquid-liquid micro-extraction.

Biosynthesis Scale-Up Process for Magnetic Iron-Oxide Nanoparticles Using Eucalyptus globulus Extract and Their Separation Properties in Lubricant-Water Emulsions.

The use of natural organic extracts in nanoparticle synthesis can reduce environmental impacts and reagent costs. With that purpose in mind, a novel biosynthesis procedure for the formation of magnetic iron-oxide nanoparticles (IONPs) using Eucalyptus globulus extract in an aqueous medium has been systematically carried out. First, the biosynthesis was optimized for various extract concentrations, prepared by decoction and infusion methods, and yielded IONPs with sizes from 4 to 9 nm. The optimum concentration was found at 5% w/v, where the biosynthesis reaction time and ammonium hydroxide amount were the lowest of all samples. This extract concentration was tested, including in replicated samples, for a scale-up process, yielded a total mass of 70 g. It was found by Rietveld and electron microscopy analyses that the structural and morphological properties, such as crystalline and particle sizes (9 nm), are equivalent when scaling the synthesis process. 57Fe Mössbauer spectroscopy results indicated that Fe ions are atomically ordered and in a trivalent state in all samples, corroborating with structural results found by X-ray diffraction. Magnetic analysis showed that the scale-up sample exhibited ferrimagnetic-like behavior suitable for magnetic remediation performance (55 emu g-1). The eucalyptus functionalization was demonstrated by thermogravimetric measurements, whereas the colloidal analysis supported the stability of the magnetic suspensions at pH = 7 (zeta potential > -20 mV). The kinetic adsorption performance indicated a fast kinetic adsorption time of 40 min and remarkable removal efficiency of 96% for lubricant removal from water (emulsion systems). The infrared analysis confirmed the presence of the eucalyptus chemical groups even after the removal experiments. These results suggest that the scale-up sample can be recovered for future and sustainable magnetic remediation processes.

Analysis of plant metabolomics data using identification‐free approaches

AbstractPlant metabolomes are structurally diverse. One of the most popular techniques for sampling this diversity is liquid chromatography–mass spectrometry (LC‐MS), which typically detects thousands of peaks from single organ extracts, many representing true metabolites. These peaks are usually annotated using in‐house retention time or spectral libraries, in silico fragmentation libraries, and increasingly through computational techniques such as machine learning. Despite these advances, over 85% of LC‐MS peaks remain unidentified, posing a major challenge for data analysis and biological interpretation. This bottleneck limits our ability to fully understand the diversity, functions, and evolution of plant metabolites. In this review, we first summarize current approaches for metabolite identification, highlighting their challenges and limitations. We further focus on alternative strategies that bypass the need for metabolite identification, allowing researchers to interpret global metabolic patterns and pinpoint key metabolite signals. These methods include molecular networking, distance‐based approaches, information theory–based metrics, and discriminant analysis. Additionally, we explore their practical applications in plant science and highlight a set of useful tools to support researchers in analyzing complex plant metabolomics data. By adopting these approaches, researchers can enhance their ability to uncover new insights into plant metabolism.

Tetradesmus obliquus organic extracts with antibacterial and antileishmanial activities

Tetradesmus obliquus organic extracts with antibacterial and antileishmanial activities

Extraction Strategies for Profiling the Molecular Composition of Particulate Organic Matter on Glacier Surfaces.

Pigmented microalgae thrive on supraglacial surfaces, producing "sticky" extracellular polymeric substances that combine into a mineral-organic matrix. Together, they enhance snow and ice melting by lowering the albedo. Understanding the chemical nature of particulate organic matter (POM) in this matrix is crucial in assessing its role in supraglacial carbon dynamics. We evaluated POM complexity in alga-rich snow and ice samples containing 0.3-6.4 wt % organic carbon (OC) via extractions with solvents of varying polarity, pH, and OM selectivity. Extraction yields were evaluated by OC analysis of the extracts, and the composition of extracted OM was analyzed using ultrahigh-resolution mass spectrometry. Individual hot water (HW), hydrochloric acid (HCl), and sodium hydroxide (NaOH) extractions achieved up to 87% efficiency, outperforming sequential, organic solvent-based extractions (<11%). OM extracted by HW, HCl, and NaOH combined had more molecular formulas (2827) than OM extracted with organic solvents (1926 formulas). Combined HW, NaOH, and HCl extractions yielded an OM composition with unsaturated, highly unsaturated, aromatic, and N-containing compounds, while unsaturated aliphatics and black carbon-derived polycyclic aromatics were enriched in the organic solvent extracts. This molecular profiling provides the first comprehensive insights into supraglacial POM composition, opening the window for understanding its role in the cryospheric carbon cycle.

Assessment of the influence of production factors on the condition of the internal organs of model animals in a 180-day experiment

The assessment of the influence of occupational factors on the state of internal organs in model conditions is becoming increasingly relevant to establish the initial manifestations of pathology at the stage of examination of the connection between the disease and the occupation of workers in harmful production conditions. The aim of the study was to assess the influence of occupational factors (at the level of 1.5 MPC, MPD) on the state of internal organs in Wistar rats under model conditions of a 180-day experiment, depending on the type and duration of their exposure. Materials and methods. In assessing the 180-day dynamics (from 0 days – 6 months (background) to 60–120–180 days – 8–10–12 months) of the impact of production factors on the morphological state of tissues and organs of Wistar rats, generally accepted and unified methods were used. Animals (n = 72) of both sexes were distributed in equal numbers (18 individuals each) into the comparison group (not exposed to production factors) and 3 experimental groups (exposure to vibration, noise, chemical exposure). Additionally, 10 individuals who were sacrificed on day 0 – 6 months (background) were allocated to the comparison group for background analysis. Every 60 days (in 180-day dynamics) after exposure to production factors, animals were euthanized with chloroform (3 ml of chloroform was injected into the desiccator with a syringe and the time from the moment of administration to the moment of onset of narcotic sleep was noted, the procedure was repeated with 5 and 10 ml of chloroform), and necropsied with organ extraction for histopathological studies. The sections were stained with hematoxylin and eosin. Results and discussion. In a chronic experiment, initial pathomorphological signs of damage in 2 or more organs were established on the 60th day of exposure to production factors, and a large degree of organ tissue damage in rats was noted from the effects of chemical and physical factors (general vibration) on the 180th day of the experiment, unlike the comparison group. Conclusions. Based on the conducted experiment on the impact of production factors (at the level of 1.5 maximum permissible concentration and maximum permissible level) on the state of the internal organs of experimental animals, it can be concluded that they develop morphofunctional disorders in 2 or more organs (biomarker of accelerated aging) on the 180th day of the experiment (with initial manifestations on the 60th and 120th days), which can provoke accelerated aging of the biological systems of animals and humans, and negatively affect their life expectancy.

Impact of Anaerobic Fermentation Liquid on Bok Choy and Mechanism of Combined Vitamin C from Bok Choy and Allicin in Treatment of DSS Colitis.

In the context of pollution-free waste treatment, anaerobic fermentation liquid (AFL), a prominent by-product of biogas engineering, has emerged as a focal point in contemporary research. Concurrently, vitamin C, an active compound abundant in fruits and vegetables, possesses extensive application potential. The development of efficient extraction processes and the utilization of its biological activities have garnered significant attention from researchers. This study investigated the impact of AFL on the growth and vitamin C content of Bok choy through field trials of varying concentrations of AFL. The results indicated that the growth characteristics of Bok choy exhibited a concentration-dependent trend with increasing AFL dosage, with the highest yield observed in the AFL-2 group (8.43 kg/m2). Additionally, with the increase in the concentration of the AFL application, the vitamin C content in Bok choy exhibited a trend of initially increasing and then decreasing, reaching its highest value (70.83 mg/100 g) in the AFL-1 group. Furthermore, response surface methodology was employed to optimize the microwave-assisted organic solvent extraction process of vitamin C, revealing that the optimal conditions for microwave-assisted extraction using a 2% citric acid solution were as follows: a microwave power of 313 W, a microwave time of 1.3 min, and a liquid-to-solid ratio of 16.4:1 v/w, achieving a vitamin C extraction rate of 90.77%. Subsequent mechanistic studies on colitis repair demonstrated that the combination of vitamin C and allicin significantly enhanced the ability of intestinal microorganisms to ferment and degrade complex carbohydrates in colitis-afflicted mice, thereby alleviating intestinal inflammation, markedly reducing bacterial invasion signals on intestinal epithelial cells, and decreasing the risk of intestinal infection. This study provides a valuable perspective for the harmless utilization of agricultural waste, and provides a theoretical basis and technical support for the high-value utilization of natural active ingredients.

Preparation of lignin-like polymers by dehydrogenation of lignin precursors and structure-activity relationships of the resulting polymers against live cancer HepG2 cells

Lignin can be used as a natural anticancer drug because of its potential biological activity and low cytotoxicity. This research focuses on oligomeric dehydrogenation polymers (DHPs) of lignin. The lignin precursor coniferin was used to yield Zulaufverfahren dehydrogenation polymers (ZL-DHPs) and Zutropfverfahren dehydropolymers (ZT-DHPs) catalyzed by mixed enzymes. The 13C-NMR determination showed that the DHPs obtained were similar to natural lignin, and ZL-DHP had a slightly higher β-5 content than ZT-DHP. ZL-DHPs and ZT-DHPs were subjected to organic solvent extraction with different polarities to obtain eight fractions, i.e., ZL-1-ZL-4 and ZT-1-ZT-4. The antitumor activity showed ZL-2 (IC50 181.99 μg/mL) and ZT-2 (IC50 246.76 μg/mL) had significant inhibitory effects. Fractions ZL-2 and ZT-2 were purified through column chromatography using gradient-polarity binary eluent, and 12 purified compounds were obtained, i.e., L1–L6 and T1–T6. The results showed L2 (IC50 33.99 μg/mL) and T1 (IC50 42.08 μg/mL) had relatively high biological activity, respectively. Their structure was characterized using high-resolution mass spectrometry and 13C-NMR, indicating that L2 is a dimer with β-5 linkage (β-5, γ-CH3, and γ’-CH2OH), and T1 is also a dimer with β-5 linkage but different substituents (β-5, γ-CHO, and γ’-COOH).

Rapid and Facile Organic Ion-Associate Liquid-Phase Extraction and Spectrophotometric Quantification of Nitrite in Environmental Water Samples

Nitrite is a health and environmental hazard and pollutes water sources globally, but sensitive, rapid, and facile quantification methods are lacking. Herein, we report a method for extracting and quantifying low-concentration nitrite in surface water using minimal sample and solvent volumes. The nitrite reacted with sulfanilamide and N-1-naphthylethylenediammonium dichloride (NED), yielding an azo dye for extraction into an organic ion-associate liquid phase (IALP) formed in situ using ethylhexyloxypropylammonium and dodecyl sulfate ions. The addition of sodium acetate increased the pH, decreasing the cation charge from +2 to +1, improving extraction efficiency. Further, adding NaCl doubled the IALP volume, reduced the required standing time, and minimally affected absorbance, and adding concentrated HCl to the IALP enhanced the absorbance intensity via dye protonation. Crucially, the method achieved a 30-fold concentration factor compared to traditional pre-treatment methods, even without centrifugation, as well as a limit of detection of 0.09 µg NO2-N/L. Spiked recovery tests with river and seawater samples (93–103%) matched those of established methods. Digital imaging of IALP-extracted lake water yielded a limit of detection of 0.4 µg NO2-N/L. The method is a sensitive, efficient approach for nitrite detection, enabling rapid environmental monitoring via spectrophotometry and digital imaging.

Capsicum chinense Jacq. fruit plays an immunomodulatory role in cytokine attenuation and DNA damage protection.

Capsicum chinense (C. chinense) Jacq., recognized for its bioactive compounds, has attracted interest due to its possible immunomodulatory and DNA-damage-protective effects. This study aimed to assess the immunomodulatory, anti-inflammatory, and DNA protection abilities of organic extracts (methanol, ethyl acetate, and petroleum ether) from C. chinense. The immunomodulatory effects were evaluated in Long Evans rats induced with SRBC. At the same time, the anti-inflammatory potential was investigated in LPS-stimulated RAW264.7 macrophages by quantifying pro-inflammatory mediators such as COX-2, iNOS, TNF-α, IL-β, and IL-6. Protective activity against DNA damage was assessed using a method that induces damage with a Fenton reagent. Cytotoxicity was tested on the Hela cell line to gauge the cellular effects of the extracts. The results demonstrated that higher doses (200 mg) of C. chinense methanol extract inhibited immune responses, whereas lower doses helped restore them. The extracts significantly decreased pro-inflammatory mediators and cytokines in LPS-activated macrophages. Both petroleum ether and methanol extracts showed higher cytotoxicity against Hela cells compared to the ethyl acetate extract. The protein levels recorded in the serological parameters were 5.74 ± 0.19, 5.36 ± 0.11, 5.74 ± 0.26, 6.02 ± 0.16, 6.18 ± 0.18, and 6.22 ± 0.20 gm/dL for NC, DC, ML, MLMExCC100, MLMExCC200, and MExCC100, respectively. These findings suggest that C. chinense extracts possess strong immunomodulatory effects and potential protection against DNA damage, supporting their therapeutic application in regulating the innate immunity system.

Determination of microplastics in municipal wastewater treatment plant effluents and sludge using micro-Raman spectroscopy

Microplastics (MPs) increase global awareness due to their ubiquity, high concentration levels, and devastating effects on the aquatic environment. Wastewater treatment plants (WWTPs) are recognized as a significant source of microplastics in aquatic and terrestrial environments, particularly for plastics used in personal care products and textile fibers from the clothing industry. The focus of the present study was the determination of MP in wastewater and sewage sludge samples of WWTP of Ioannina city, according to their shape, size, concentration, and polymer type. A wet peroxide oxidation (WPO) method using 30% H2O2 and 0.05 M ferrous (II) solution was applied to the water effluent, while an enzymatic digestion method combined with WPO was employed to eliminate the organic matter and extract MPs from sludge samples. Micro-Raman spectroscopy coupled with appropriate software was applied to detect and quantify the microplastic particles. The outcomes from this study showed that the most representative shape of MP in effluent wastewater and sludge was fragments (66.7% and 75%, respectively), followed by fibers, spheres, and films. Polyamide (PA), p -acrylic acid (PAA), and p -acrylamide-co-p -acrylic acid (PAM-co-PAA) were the most abundant polymers (100% frequency of detection), followed by p -vinyl chloride (PVC), p -butyl methacrylate (PBMA), p -ethylene (PE), p -styrene (PS), p -propylene (PP), p -vinyl alcohol (PVA), and p -vinyl butyral (PVB) (20%-80% frequency of detection). The mean concentration of MPs in five sampling campaigns was 5.8 ± 0.6 particles/L in secondary WWTP effluents and 33.3 ± 8 particles/g in sludge. This study focused on monitoring campaign, in order to better understand the occurrence, impact, and risks associated with MPs on WWTPs.

Vasorelaxant and Antihypertensive Effects of Extracts from the Leaves of Casimiroa edulis La Llave (Rutaceae) by NO Release and Calcium Channel Blockade.

Casimiroa edulis La Llave (Rutaceae), commonly known as "zapote blanco", is a tree widely distributed in the tropical and subtropical areas of Mexico. The decoction of its leaves is traditionally used as a natural remedy to treat hypertension and anxiety. The present study aimed to determine the vasorelaxant and antihypertensive effects of C. edulis extracts and evaluate the acute and sub-acute toxicity of one of the most active extracts. The hydro-alcohol and organic (hexane, dichloromethane, and methanol) extracts, obtained from the leaves of C. edulis, were evaluated on isolated aorta rat rings in the presence and absence of endothelium to determine their vasorelaxant effect. Then, most active extracts were studied to evaluate the functional mechanism of their vasorelaxant action and antihypertensive effect on spontaneously hypertensive rats (SHR). The acute and sub-acute toxicity of dichloromethane extract was evaluated following the OECD 423 and 407 protocols. The hexane (HE) and dichloromethane (DE) extracts from Casimiroa edulis induced significant vasorelaxant action on isolated rat aortic rings with (Emax 104.7 ± 1.4% and Emax 97.3 ± 6.7%, respectively) and without (Emax 94.9 ± 3.5% and Emax 67.4 ± 1.0%, respectively) endothelium, and this effect was partially endothelium-dependent. Their vasorelaxant action was modified by L-NAME (nitric oxide synthase inhibitor) and ODQ (soluble guanylyl cyclase inhibitor); however, indomethacin did not modify the effect. Also, both HE and DE significantly decreased the contraction induced by KCl in a concentration-dependent manner and the maximal effect induced by CaCl2. Moreover, DE showed a significant decrease in systolic and diastolic blood pressure in SHR at 7 hours and 15 days after treatment, respectively. Finally, the toxicity test of DE allowed classifying it in category 5, indicating it to be a non-toxic extract based on OECD guideline 423; the LD50 value was estimated to be greater than 2,000 mg/Kg and smaller than 5,000 mg/Kg in Wistar rats. The results demonstrated hexane and dichloromethane extracts to exert a vasorelaxant effect through endothelium-dependent NO release and cGMP increase, as well as by calcium channel blockade. Also, dichloromethane extract showed efficacy and security as a potential antihypertensive agent.

Marmaricines A-C: Antimicrobial Brominated Pyrrole Alkaloids from the Red Sea Marine Sponge Agelas sp. aff. marmarica.

The Red Sea is the home of a rich diversity of sponge species with unique ecological adaptations that thrive in its saline, warm, and nutrient-poor waters. Red Sea sponges offer potential as sources of bioactive compounds and novel drugs. The organic extract of the Red Sea sponge Agelas sp. aff. marmarica was investigated for its antimicrobial constituents. Through bioassay-guided fractionation of the antimicrobial fraction of the extract on SiO2 and Sephadex LH-20, as well as HPLC purification, three bioactive compounds, marmaricines A-C (1-3), were isolated. Structural elucidation of the compounds was performed using 1D (1H and 13C) and 2D (COSY, HSQC, HMBC, and NOESY) NMR, as well as (+)-HRESIMS, leading to the identification of the compounds. The antimicrobial activities of the compounds were assessed through evaluation of their inhibition zones, MIC, MBC, and MFC, against Methicillin-Resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans. Marmaricines A and B exhibited the strongest antibacterial effects against MRSA, with inhibition zones ranging from 14.00 to 15.00 mm, MIC values of 8 µg/mL, and MBC values of 16 µg/mL. In comparison, marmaracine C showed slightly weaker activity (inhibition zone: 12 mm, MIC: 16 µg/mL, MBC: 32 µg/mL). In terms of antifungal activity, marmaricines B and C demonstrated the greatest effect against C. albicans, with inhibition zones of 14-15 mm, MIC values of 8 µg/mL, and MFCs of 16 µg/mL. Interestingly, none of the compounds showed any inhibitory effect against E. coli. The results indicate that marmaricines A-C are selectively active against MRSA, and marmaricines B and C demonstrate potential against C. albicans, making them promising candidates for the development of novel antimicrobial agents targeting resistant pathogens.

Synergistic effects of seaweed extract presoaking and foliar spray on the performance of paddy improved kavuni (CO 57)

Rice (Oryza sativa L.) is a staple food crop and a primary source of sustenance for more than half of the world's population. Seed treatments and foliar applications have emerged as effective methods to enhance growth and yield attributes. In this study, improved kavuni (CO 57) seeds were used for a field experiment conducted during the Samba season (2023). The experiment was designed using a Factorial Randomized Block Design with 15 treatments and three replications, focusing on foliar spray applications. The primary objective was to evaluate the impact of Sargassum myricocystum, Kappaphycus alvarezii methanol extract and foliar spray on rice growth and productivity. The results revealed that the combined application of presoaking seeds in 0.5 % Sargassum myricocystum methanol extract with a foliar spray of 2.5 % seaweed extract at the panicle initiation and flowering stages (T1F2) significantly enhanced plant growth and yield parameters. Higher plant height (121 cm), leaf area index (4.85), dry matter production (5180 kg ha- ¹), productive tillers (281 m- ²), filled seeds per panicle (170), 1000 seed weight (22.34 g), seed yield (4552 kg ha- ¹) and straw yield (6370 kg ha- ¹) were recorded under T1F2 compared to other treatments. The use of organic input seaweed extracts, improved plant quality and yield sustainably without harming the natural ecosystem. This study highlights the significant potential of seaweed extracts in enhancing overall crop performance, leading to optimal plant growth characteristics and yield attributes. The findings emphasise the role of organic inputs in promoting sustainable agriculture, contributing to environmental conservation while supporting food security.